This Application claims priority of Taiwan Patent Application No. 96130161, filed on Aug. 15, 2007, the entirety of which is incorporated by reference herein.
1. Field of the Invention
The present invention relates generally to a fan system and a motor control device and more particularly to a fan system and a motor control device with two-way operation in a same transmission route by integrating a motor rotation speed signal and a rotation speed control signal of the fan system.
2. Description of the Related Art
A fan used as a heat-dissipating device is a common structure setting. For the usage of clients, increase or decrease of fan number usually depends on various requirements of clients. Additionally, in a fan, the rotation speed of a motor is driven and controlled by a controller or a control chip, thereby adjusting the rotation speed of the fan in the correspondence of the actual operation condition of clients.
Referring to FIG. 1, a conventional fan system is constituted by a fan device 14 and a control device 15 (controlled by clients), wherein the fan device 14 is electrically connected to the control device 15. The fan device 14 is constituted by a motor driving circuit 21, a motor 22, and a fan 23. The control device 15 generally is constituted by a pulse width modulation generation circuit 11 and a rotation speed reading circuit 12.The pulse width modulation generation circuit 11 and the rotation speed reading circuit 12 are electrically connected to the motor driving circuit 21 of the fan device 14 respectively for setting up a first transmission route 10 and a second transmission route 20. In addition the pulse width modulation generation circuit 11 generates a pulse width modulation (PWM) signal to the motor driving circuit 21 via the first transmission route 10 for control of the motor 22 and the fan 23 of the fan device 14 based on the PWM signal. Morevoer, the rotation speed signal of the fan device 14 returns to the rotation speed reading circuit 12 via the second transmission route 20 such that the control device 15 may obtain the actual rotation speed value of the motor 22 and the fan 23 of the fan device 14. Said motor driving circuit 21 is electrically connected to the pulse width modulation generation circuit 11 and the rotation speed reading circuit 12 respectively for receiving the pulse width modulation signal and transmitting the rotation speed signal of the motor 22. Therefore, the above-mentioned signals are operated independently.